Michael Tipton of the University of Portsmouth added another source to the picture: fish eyes. Fish eyes are rich in several nutrients that become depleted during extended survival situations, including vitamin C and certain B vitamins. They are not a pleasant food by any conventional standard, but Alvarenga was not operating by conventional standards. He was consuming fish eyes as a routine part of using a fish fully — an approach consistent with the practice of experienced fishermen who know that nothing from a catch should go to waste.
The cumulative picture is of a diet that, while extremely limited and entirely composed of raw animal protein, happened to provide the specific nutrients most critical to survival in an ocean environment. This was not luck; it was the application of knowledge about what the ocean contains and how to use it. The specific foods Alvarenga ate were the specific foods available to him, but his choice to eat them fully — including the organs and the eyes that a less experienced person might discard — was a knowledge-based choice that had survival consequences.
## Ebon Atoll: The Accident of Geography
The Marshall Islands consist of 29 atolls and 5 islands scattered across approximately 750,000 square miles of the central Pacific Ocean. In terms of land area, the entire chain comprises roughly 70 square miles — an extraordinarily small target in an extraordinarily large body of water.
Ebon Atoll is the southernmost of the chain. It sits at approximately 4.5 degrees north latitude and 168 degrees east longitude — at the southern end of the Marshall Islands and at the western end of the range that the University of Hawaii’s drift model predicted for a boat leaving the Mexican Pacific coast in late 2012.